杨超, 董浚键, 刘志刚, 孙成飞, 赵飞, 叶星. 大口黑鲈源维氏气单胞菌的分离鉴定[J]. 南方水产科学, 2021, 17(3): 54-61. DOI: 10.12131/20200230
引用本文: 杨超, 董浚键, 刘志刚, 孙成飞, 赵飞, 叶星. 大口黑鲈源维氏气单胞菌的分离鉴定[J]. 南方水产科学, 2021, 17(3): 54-61. DOI: 10.12131/20200230
YANG Chao, DONG Junjian, LIU Zhigang, SUN Chengfei, ZHAO Fei, YE Xing. Isolation and identification of Aeromonas veronii from diseased Micropterus salmoides[J]. South China Fisheries Science, 2021, 17(3): 54-61. DOI: 10.12131/20200230
Citation: YANG Chao, DONG Junjian, LIU Zhigang, SUN Chengfei, ZHAO Fei, YE Xing. Isolation and identification of Aeromonas veronii from diseased Micropterus salmoides[J]. South China Fisheries Science, 2021, 17(3): 54-61. DOI: 10.12131/20200230

大口黑鲈源维氏气单胞菌的分离鉴定

Isolation and identification of Aeromonas veronii from diseased Micropterus salmoides

  • 摘要: 为查明2020年春季广东省佛山市某养殖场人工养殖大口黑鲈 (Micropterus salmoides) 鱼苗出现暴发性死亡的病因,该研究对患病大口黑鲈鱼苗肝脏组织中分离的一株细菌GZXR2020进行了分子鉴定,PCR扩增获得该菌株的16S rRNA基因和gyrB基因全长序列,BLAST显示其与维氏气单胞菌 (Aeromonas veronii) 的相应序列高度同源,同源性分别高于99.5%和98.3%。根据VITEK2全自动细菌鉴定系统45个理化项目的鉴定结果、羊血琼脂平板溶血实验呈β-溶血的结果,进一步通过毒力基因检测并结合补充理化鉴定结果,可判断此分离菌株为维氏气单胞菌温和生物型 (A. veronii bv. sobria)。人工回归感染实验采用低、中、高3种菌液浓度 (3×107、1.5×108和3×108 CFU·mL−1) 进行腹腔注射攻毒,可分别导致7%、40%和100%的死亡率,证实维氏气单胞菌温和生物型是引起此次大口黑鲈暴发性死亡的致病原。药物敏感性实验显示,在所检测的17种抗菌药物中,该菌株对大观霉素、氟罗沙星、氟苯尼考等7种药物敏感。

     

    Abstract: Sudden death occurred in Micropterus salmoides larvae reared on a farm in Foshan, Guangdong Province of China in spring of 2020. To investigate the etiology of this disease, we isolated a strain of bacteria GZXR2020 from the liver tissue of diseased M. salmoides larvae and conducted its molecular identification. We obtained the full-length sequences of the 16S rRNA gene and gyrB gene of the strain by PCR amplification. BLAST results show that the sequences were highly homologous to the corresponding sequence of Aeromonas veronii in GenBank, with homology higher than 99.5% and 98.3%, respectively. Using VITEK2 automatic bacterial identification system and according to the results of a total of 45 physical and chemical identification, sheep blood agar plate hemolysis test that showed β-hemolysis, detection of the virulence genes as well as the physicochemical identification, we identified the bacteria as A. veronii bv. sobria. In the artificial regression infection experiment, intraperitoneal injection of 3×107, 1.5×108 and 3×108 CFU·mL−1 resulted in 7%, 40% and 100% mortality, respectively. The drug sensitivity test of a total of 17 antimicrobial agents shows that the strain GZXR2020 was highly sensitive to seven antibacterial drugs such as spectinomycin, fleroxacin, florfenicol and so on.

     

/

返回文章
返回